Shock-absorber.



D. P. KILGOUR.

SHOCK ABSORBER. APPLICATION FILED'SEPT. 27, 1909.

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v To all whom itmay concern:

UNITED sTATr Es PATENT orFIoE.

DWIGHT F. KILGOUR, OF LEXINGTON, MASSACHUSETTS;

'sHooizizsonnnn.

Specification of Letters Patent.

Patcnted' Feb. 14, 19311.

Application filed September 27, 1909. Serial No. 519,682.

Be it knownthat I, Dwicrrr F. KiLooUR, a citizen of the United States, and a resident of Lexington, in the county of Middlesex and Commonwealth of Massachusetts, have invented an Improvement in Shock-Absorbers, of which the following description, in

connection With the accompanying drawings,

' is a specification, like letters on the drawings re resenting like parts.

his invention relates to shock absorbers for automobiles and other vehicles.

The character of the invention may be best understood by reference to the following description of an illustrative embodiment thereof shown in the'accompanying drawings, wherein:

Figure 1 is a vertical section through a shock absorber embodying my invention;

andFig. 2 is a transverse section taken on line 2-2 of Fig. 1

Referring to the drawings the illustrative shockabsorber herein shown as embodying my invention comprises a cylindrical easing 3 having its ends threaded into cylinder lieads.5. Within the casing 3 is introduced a hollowcylinder or chamber 9 of somewhat smaller diameter thansaid casing, an annular chamber 11 being formed between the two. This cylinder is not permanently pos1= tioned Within said casing, but is removably fromthe cylin 1 inlls aid cylinder in response to the move- 'joint 25.

ments of the vehicle body or chassis, the upper end of the piston may be connected to a:suitable bracket on the chassis or body of theyehic'le by a universal joint 23,While the lower cylinder head 5 may be connected to a suitable bracket on the axle or on the under side of the vehicle spring by a universal To impede-or resist the movement of the piston within the cylinder or chamber 9, the latter and the annular chamber 11 may be filled with oil or any other fluid as deegress of the oil from said cylinder.

sired. The oil may be introduced into the.

casing through filling holes 97 which may be closed by screw 29.

To permit the oil or fluid to escape from said cylinder into the annular chamber and circulate from one to the other as the piston reciprocates the wall of said cylinder may be discontinuous, perforated or foramimited.

'To increase the resistance to. the escape. of

the oil or fluid from said cylinder, in proportion to the piston movement said cylinder is divided into a plurality of zones, each having comparatively small perforations of different areas. five such zones being shown herein, comprising a central zone (1., zones b above and beneath the latter and zones 0 adjacent the zones 1). ,lVhen the vehicle is passing over smooth roads the vehicle springs do not receive great shocks and the piston reciprocates with slight movements in zone a. To provide little or no resistance 'to the piston under these conditions the zone c is provided with large perforations 32,

permitting the 'oil to readi y escape therethrough when pressed by the piston.

When the vehicle is assing over rough roads or obstacles, the piston reciprocations are. greater and the piston would pass beyond zone a into zones 1). This zone is provided with perforations 3% which are smaller than those in zone a and resist the As a result the movement of the piston is impeded or cushioned.

When unusually rough roads or unusually large obstacles are passed over the piston may pass beyond the zones 1) intozones c. To offer still greater resistance to the piston in the latter zones, the perforations 36 are provided, smaller than those in the zones 1).

Each zone contains a multiplicity of open- .ings distributed laterally of the cylinder andgraded longitudinally of the latter to provide a gradually.reduced total area of opening 1n each zone and also provide a gradually reduced total area of opening exends of the cylinder.

The multiplicity of the comparatively small openings presents distributed fluid controlling friction surfaces, resisting the egress of oil through the wall of the cylinder at widely distributed points and thereby furnishes a very advantageous control over the piston throughout its movements.

It will be observed that in each of the tending from the central zone toward the 15 locally reduced opening.

zones is provided a row of openings (here in four are shown on each side of the cylinder) adjacent'the zone. 6 furnishing a total opening less than that in the lateral rows directly above and beneath thesame. As a.

result when the piston is suddenly moved toward either end of the cylinder the locally reduced opening formed by said rows of four openings momentarily increases the re- 10 sistanceto the passage of the fluid through the cylinder and momentarily checks the piston. Rebound of the latter is prevented by the larger total opening presented by the longer row of openings directly beyond said The continued movement'of the piston is then gradually retarded by the taper or-gradation of the openings in the zone 0.

The resistance to the egress of the oil in any or all of the zones may beyaried not only by varying the sizes or areas of the perforations, but by varying their frequency of distribution. that if the perforations are arranged in rows, the number of perforations in the rows more remote from the central portion of the cylinder may be made less than in the rows in the central portion 40 oil always fills the annular chamber and cylinder but that its circulation will depend \upon the movement of the piston within the cylinder and the freedom with which the oil is permitted to pass from the cylinder into the annular chambcr. To permit the oil to pass beneath-the piston beyond the limit of the perforations in the zones 0 and to vary the pressure ofthe oil or fluid within the casi ifg...ancl cylinder the upper and lower I cylinder heads may be each provided with ports 37 communicating withthe cylinder and the annular chamber, the opening of said ports being regulated by adjusting screws38.

To iroyide a shock absorber which may be adaptable to heavy or light vehicles and whichmay be readily adjustable to vary the resistance to the circulation of the oil to meet varying conditions as required, 'the effective areas of the perforations in the zones referred to may be varied. To this end the zones 0.. b, (j 21.18 provided with ad.- justing rings a, 1/, 0 respectively, which encircle the cylinder 9 opposite to their respective zones and may be provided with perforations corresponding to the perforations in the cylinder zones; "It will be obvious that by turning said rings about saidf cylinder their perforations may be brought in accurate registration with the perfora-. 7 0 tionsin said cylinder or said ..rings may be turned to destroy the-exact registrationof said perforations to a greater or less extent as desired. Herein the adjusting rings may be turned into four positions of adjustment and may be held in these positions by a pair of screws 39 threaded into each of said rings at opposed points, said screws being adapted to be set into the threaded holes 41 to give the adjustment desired.- As shown'in'Fig.

2, the cylinder is provided with four perforations on teach side, correspondingto seven perforations on opposite sides of the ring thereof. The screw holes 41 in'sa id cylinder are not spaced at even distances apart but. herein the screw holes 41", 41 are one-fourth of an inch. apart; the screw holes ll; ll. are nine thirty-seconds of an inch. apart; and the screw holes ll, all are'livesixteenths of an inch apart. 'As a result by turning a ring about the cylinder 9 to bring the screws 89 in registration with the va rious screw holes 41 al 41 and 41 the cylinder perforations may be cut off more or v less to'vary the freedom of fluid flow therethrough as desired. By the use of a separate ring for each zone the effective, areas of the perforations in the various zones maybe independently adjusted.

To permit the ad'ustment of the rings the cylinder 9 may be removed from the casing 3 by simply unscrewing one of the cylinder heads which will permit the 'ready .withdrawal of the cylinder therefrom. The rings may then be adjusted to give the area of perforation desired and the cylinder returned within the casing and the cylinder head.

threaded thereon to hold the cylinder in place. I

By my invention is provided a shock 'absorber which has no valves, springs or. other parts which will-beliable towork loose" or get out of order.

The device may be readily applied to.

heavy or light vehicles and adjusted to rerality of openings distributed laterally of 3 said chamber and graded longitudinally of the latter; and means movable in said chamber and controlled by the resistance otl'ered by said openings to the passage of said tluid therethrough.

2. A shock absorber comprising, in combi nation, a fluid containing chamber having a multiplicity of comparatively small openings distributed laterally of said chamber and graded lmigitudinally of the latter to present distributed fluid controlling friction surfaces of substantial total extent, and means reciprocable in said chamber against .the resistance ofi'ered by said openings to friction surfaces of substantial total extent,

ciprocable in one of said chambers against and means reciproeable in said chamber against the resistance .otlered by said openings to the passage of said fluid theretln'ough. at. A shock absorber comprising in combination, fluid containing chambers having a Wall between them containing comparatively small openings providing communication between sald chambers, said openingsbeing distributed laterally of said wall and graded longitudinally of the latter/to pre sent distributed fluid controlling friction surfaces of substantial extent; and means rethe resistance oll'ered by said openings to the passage of fluid to and from said chambers.

5. A shock absorber comprising, iii combination, a fluid containing chamber having a multiplicity of comparatively small openings distributed laterally thereof and graded longitudinally thereof, some of said openings being arranged to present a locally reduced opening area, and means reciprocable in saidchamber momentarily checked by the increased resistance oll'ered to the passage of said lluid through said locally reducedarezn 6. A shock absorber comprising in combination, lluid containing chambers having an apertured wall common thereto; means reciprocable in one of said chambers against the resistance offered to the passage of fluid through saidwall, and a plurality of rings on one of said chambers for adjusting the effective areas of the apertures in said wall.

7. A shock absorber comprising, in combinat ion, a fluid'a-onta ining ehambcrprovided with a wall having apertured zones, means independently to adjust the apertured areas of the ditl'erent zones, and means reciprocable in said chamber against the resistance offered by said apertured Zones to the pas sage of said fluid therctln'ough.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

DWIGHT F. KILGOUR. lVitnesses:

EVERETT S. EMERY, 1 ROBERT H. KAMMLER. 

